1. Field of the Invention
The present invention relates to an electrical apparatus such as a power adapter and particularly to a technique for improving strength of a case housing a circuit board.
2. Description of the Related Art
Conventionally, electronic devices such as portable game devices and portable personal computers are used (for example, U.S. Patent Application Publication No. 2007/0202956). The electronic devices are supplied with power through a power adapter when these devices are charged or used. The case of an electrical apparatus such as a power adapter is often formed by combining two members (hereinafter referred to as half cases) each of which has a shape obtained by halving a box. Edges of the two half cases are welded to each other, for example, by ultrasonic welding.